Process heat exchanger dimensioning

[AO1958]

Hello there,

I am focusing in a new design and I found a very strange issue:

I have to dimension an heat exchanger.
What really puzzles me is that not both inlet temperatures are provided, but one inlet temperature and the max value for the outlet temperature of hot fluid.
Capacity is specified, and both fluid fluxes, too.
The design refers to a process cooler.
I find it a really strange problem, since e-ntu method can't be utilized directly.

One possible solution is to get hot fluid inlet temperature by capacity, fluid and outlet temperature. Then, applying e-ntu method.



Anyhow, I'd like to know if anybody has ever faced to a similar problem and if there is a different method than the one I considered.

Many thanks

 

[sheiko]

Hi,

You have failed to provide the basic data of your problem, anyway I don't see anything strange in your problem. To solve it, two flow rates and three temperatures may be specified. Then, the fourth temperature (hot outlet temperature) may be calculated with a heat balance. Make sure it does not exceed the max. value.


"We don't believe things because they are true, things are true because we believe them."

 

[MechEngNCPE]

Specify the delta t for the one fluid, then do energy balance to find the hot exit temp on the other fluid.